Double Offset Surgical Tool Handle Assembly Having A Locking Linkage Aligned Along Two Different Planes

ABSTRACT

A surgical tool handle for releasable connection to a surgical tool is described. The tool handle comprises a housing providing a linkage chamber extending from a proximal housing grip end to a distal housing tool end for receiving a surgical tool. A tool linkage is partially housed within the housing linkage chamber comprising an axial handle region extending along axis A-A and a radiused housing region curving about a focal point. That way, a locking pawl of the tool linkage changes planes from its proximal end to a distal extending hook end. This provides a relatively short connection to a surgical tool that is optimum in the tight space requirements of a minimally invasive hip surgery.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. provisional application Ser.No. 61/310,741, filed on Mar. 5, 2010.

FIELD OF THE INVENTION

This invention relates to surgical tools for aiding in the installationof orthopedic prostheses in patients. More particularly, the presentinvention relates to an easily sterilizable handle assembly for use witha surgical tool in preparing a bone site, and for use in installing aprosthesis in the bone.

BACKGROUND OF THE INVENTION

Complicated surgical tool handles typically have crevices and recessesthat are difficult to clean with relative ease without disassembly intoseparate component parts. Tool handles that are not properly cleaned andsterilized increase the risk of disease transfer from patient topatient. This is especially true following the emergence of certain“prions” that are not killed by normal hospital sterilization. A prionis a type of infectious agent made only of protein.

Further, in surgical procedures in which access to the treatment site islimited, it is difficult to use current solutions without subjecting thepatient to repeated abrasion and tissue trauma when inserting andextracting surgical instruments.

Additionally, the insertion of a prosthetic implant is oftenproblematic, and the orientation of the implant in a properly preparedrecess is often critical to minimize recovery time of the patient. Stillfurther, once the appropriate position of the tool is selected, it isoften difficult to ensure that the position does not change uponinsertion of the assembly through the incision.

It would be beneficial, therefore, to have an orthopedic tool handlethat easily connects to a surgical tool, and that is readily adjustable,disassemblable, and cleanable. Additionally, it would be beneficial ifthe tool were partially disassembled for cleaning without the need tocompletely the component parts of the handle from each other. Further,it would be beneficial to have a handle that enables the surgeon tobetter maneuver and position a tool head to facilitate preparing a bonesite to receive a prosthetic implant in a particular angularorientation.

SUMMARY OF THE INVENTION

A surgical tool handle aids a surgeon in controlling the use of a toolduring surgery, for example, during preparation of a femoral cavity forreception of hip joint prosthesis. The present invention is such asurgical tool handle, but adapted to facilitate sterilization. That way,the present toll handle allows for partial disassembly to facilitatesterilization, while remaining loosely intact to prevent the separationof component parts from the device as a whole.

The present surgical handle comprises a housing providing a linkagechamber housing a tool linkage. The housing extends from a proximalhousing grip end to a distal housing tool end for receiving a tool. Thetool linkage comprising: a handle lever attached to the housing by aproximal housing pivot pin to thereby provide a first pivotableconnection between the tool linkage and the housing; a locking pawlattached to the housing by a distal housing pivot pin to thereby providea second pivotable connection between the tool linkage and the housing;an inverted linkage comprising a proximal inverted linkage end and adistal inverted linkage end connected by a first free pivot pin to thehandle lever to thereby provide a third pivotable connection; and a mainlinkage comprising a proximal main linkage end connected by a secondfree pivot pin to the proximal inverted linkage end adjacent to theproximal housing end in a fourth pivotable connection and a distal mainlinkage end connected by a third free pivot pin to the locking pawladjacent to the distal housing end in a fifth pivotable connection.

During use, the handle lever is pivotable about the proximal housingpivot pin from a first, opened position spaced a maximum distance alonga range of motion from the proximal housing end to a second, closedposition spaced at a closer distance along the range of motion relativeto the proximal housing end than the first position. This movementcauses the inverted linkage, connected to the handle lever by the firstfree pivot pin, to move in a proximal direction to thereby move the mainlinkage, connected to the inverted linkage at the second free pivot pin,in a proximal direction toward the proximal housing end. This causes thelocking pawl, connected to the distal main linkage end by the third freepivot pin, to pivot with respect to the housing on the distal housingpivot pin from an open configuration ready to receive a surgical toolfor attachment to the housing to a closed configuration engageable witha surgical tool supported at the distal housing tool end.

In that respect, the present handle assembly is an adapted instrumentused to prepare a cavity of the femur during a minimally invasive hipsurgery. For that purpose, the handle assembly is adapted for ananterior approach where the locking pawl that detachably connects to asurgical tool, such as a rasp handle, changes planes from its proximalto distal ends. This provides a relatively short connection to thesurgical tool that is optimum in the tight space requirements of aminimally invasive surgery.

These features of the present invention will be apparent uponconsideration of the following detailed description in connection withthe following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a surgical tool handle assembly 10according to the present invention connected to a surgical tool 12.

FIG. 2 is a side elevational view of the handle assembly 10 shown inFIG. 1 connected to a surgical tool 12.

FIG. 3 is a plan view of the handle assembly 10 of FIG. 1 connected to asurgical tool 12 and showing alternate right and left bend embodiments.

FIG. 4 is a broken-away view of the handle assembly 10 shown in FIG. 1prior to connection to a surgical tool 12.

FIG. 5 is a side, cross-sectional view of the handle assembly 10 priorto connection to the surgical tool 12.

FIG. 6 is a side, cross-sectional view of the handle assembly 10 afterhaving been connected to the surgical tool 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to the drawings, FIGS. 1 to 6 illustrate a surgical toolhandle assembly 10 according to the present invention. The handleassembly 10 is shown connected to a surgical broach or rasp 12 forperforming a minimally invasive hip replacement surgery. Other toolsuseful with the handle assembly 10 include, but are not limited to,reamers, angled drivers, twist drills, flexible drills, cannulateddrills, bayonet drills, bayonet taps, drill guides, adjustable angledrill guides, taps, and cannulated taps.

The handle assembly 10 generally comprises a linkage train 14 disposedwithin a housing 16. The housing 16 had a length that extends from aproximal housing section 18 to a distal neck section 20 with anintermediate housing section 22 there between. The intermediate housingsection 22 comprises spaced apart right and left side walls 24 and 26extending upwardly from a bottom wall 28 to an upper opening 30.

A unique feature of the present handle assembly 10 is that theintermediate housing section 22 is further comprised of an axial housingregion 22A aligned along the axis A-A and a radiused housing region 22B.As particularly shown in FIG. 3, the radiused housing region 225provides the side walls 24, 26 with a radiused contour centered about afocal point 32, 32′. The radiused housing region 22B can curve in eithera leftward direction or a rightward direction (shown in dashed lines).This construction provides the intermediate section 22 having a linkagechamber with a generally U-shaped cross-section perpendicular to axisA-A and along the curvature of the radiused region 22B extending fromthe proximal housing section 18. The bottom wall 28 is planar along theproximal housing section 18 and the axial housing region 22A. Further,the intermediate housing section 22 not only curves either to the rightor left, depending on the embodiment, but downwardly along the radiusedregion 22B as well.

A pair of aligned slots 34A, 34B, serving 2S catch recesses, extendsfrom the upper opening 30 part-way into the height of the respectiveside walls 24, 26. A recess 36 is provided in the bottom wall 28vertically below the aligned slots 34A, 34B. A pair of side-by-sidevertical bores 38A, 38B (FIG. 3) extends from the recess 36 to the upperedges of the side walls 24, 26 proximally, but adjacent to therespective aligned slots 34A, 34B. The significance of the aligned slots34A, 34B, the recess 36, and the vertical bores 38A, 38B will bediscussed hereinafter.

The intermediate housing section 22 seamlessly meets the proximalhousing section 18 having a generally rectangular shape in cross-sectionperpendicular to the axis A-A provided by the right and left side walls24, 26, the bottom side wall 28 and an upper side wall 40. The upperside wall 40 is contoured to provide a finger grip region 42 adjacent toa ledge 44. A strike plate 46 is connected to the end of the proximalhousing section 18.

The radiused region 22B of the intermediate housing section 22 extendsin a downwardly direction until it meets the distal neck section 20aligned along a second axis B-B (FIGS. 1 and 3). Axis B-B is parallelto, but spaced from, the axis A-A. In that manner, the right and leftside walls 24, 26 forming the intermediate housing section 22 seamlesslyextend distally and downwardly to form the distal neck section 20 of thehousing. However, the bottom wall 28 ends spaced from the distal necksection 20. This provides a distal lower open slot 48 (FIG. 5) that isvertically below that portion of the upper opening 30 residing in thedistal neck section 20. At the end of the distal neck section 20, theright and left side walls 22, 26 meet a nose 50 (FIG. 4) supporting areinforcing extension 52 vertically below a nose opening 50A.

As shown in FIGS. 1 to 4, the linkage train 14 resides inside thehousing 16 and comprises a handle lever 54, a main linkage 56 and alocking pawl 58. The handle lever 54 includes a distal head 60supporting a main fulcrum pin 62 having opposed ends extending outwardlyfrom the handle lever head in an orientation aligned perpendicular toaxis A-A. The opposed ends of pin 62 are received in the respectiveslots 34A, 34B while a proximal end 54A of the handle lever 54 rests onledge 44. Moving in a proximal direction from the main fulcrum pin 62,the handle lever head 60 divides into spaced apart side walls 60A, 60Bproviding a gap there between.

The main linkage 56 is an elongate member having a proximal section 56Awith its end received in the gap formed by the spaced apart side walls60A, 60B (FIG. 6) of the handle head 60. The main linkage 56 ispivotably connected to the handle head 60 by a pin 64 located proximallyof the fulcrum pin 62 (FIG. 6).

The proximal section 56A of the main linkage 56 is aligned with theaxial region 22A of the intermediate housing section 22 along axis A-A.From there, and in a similar manner as the overall contour of theintermediate housing section 22, the main linkage 56 curves into anintermediate radiused portion 56B that coincides with the radiusedregion 22B of the intermediate housing section until it forms into adistal portion 56C.

The locking pawl 58 is a relatively short member extending from a forkedproximal end 66 to an upwardly extending hook 68. The proximal end 66 ofthe locking pawl 58 is pivotably connected to the distal portion 56C ofthe main linkage 56 by a second pivot pin 70. Further, a housing pivotpin 72 extends through the locking pawl 58 at an intermediate locationbetween the proximal end 66 and the upwardly extending hook 68. Theopposed ends of the housing pivot pin 72 are received in openings in theright and left housing side walls 24, 26 flush with the respective outersurfaces thereof. That way, the hook 68 of the locking pawl 58 ispivotable about a range of motion with respect to the nose opening 50Aof the housing 16.

With the linkage train 14 residing inside the right and left side walls24, 26 and the bottom wall 28 comprising the housing 16, the mainlinkage 56 extends from the axial housing region 22A of the intermediatehousing section 22 at a position adjacent to the proximal housingsection 18, along the radiused housing region 22B and to the distalhousing neck section 20. The distal neck section 20 is where the mainlinkage 56 pivotably connects to the locking pawl 58. Importantly, thelocking pawl 58 changes planes from its proximal end 66 to distalextending hook end 68. This provides a relatively short connection tothe surgical tool 12 that is optimum in the tight space requirements ofa minimally invasive surgery.

As previously discussed, the proximal portion 56A of the main linkage 54is pivotably connected to the handle lever 52 at the pivot pin 64, whichis proximal of the main fulcrum pin 62 pivotably received in therespective slots 34A, 34B of the right and left side walls 24, 26 of thehousing 16.

As particularly shown in FIGS. 2, 3, 5 and 6, a linkage lock mechanism74 comprises a base plate 74A having a pair of opposed upwardlyextending blocking pins 74B, 74C supported thereon. When the linkagetrain 14 resides in the housing 16 with the main fulcrum pin 62 seatedin the slots 34A, 34B, the linkage lock mechanism 74 is moved intoposition with the blocking pins 74B, 74C residing in the bores 38A, 38Bin the respective side walls 24, 26. With the base plate 74A seated inthe housing recess 36, the distal ends of the pins 74B, 74C extendupwardly beyond the upper edges of the side walls 24, 26. Theseextending portions of pins 74B, 74C block the fulcrum pin 62 and,consequently, the linkage train 14 from being removed from inside thehousing 16. It should be noted that the pivotable connection between thelocking pawl 58 and the distal neck section 20 of the housing 16 at pin72 prevents the linkage train 14 from being completely separate from thehousing.

Because they are supported on side walls comprising the housing, thefulcrum pin 62 and the pivot pin 72 are referred to in the claims as“housing pivot pins”. That is regardless whether they are intended to beremovable from their supported relationship with the housing, as in thecase of fulcrum pin 62, or not, as in the case of pivot pin 72. Theother pivot pins 64 and 70 are referred to as “free pivot pins”. That isbecause those latter pivot pins provide for pivotable movement, betweenthe various linkage members they connect together without beingsupported on the housing.

In use, the handle assembly 10 is detachably connectable to a surgicaltool 12, such as a broach or rasp, by lifting the handle lever 54 in anupwardly direction (arrow 100, FIG. 5), away from the housing ledge 44.Manipulation is aided by the finger recess 42. As the proximal end ofthe handle lever 54 moves upwardly, its handle head 60 pivots on thefulcrum pin 62 received in the aligned slots 34A, 34B. This movementcauses the pivot pin 64 to move upwardly and distally to a positionessentially vertically aligned directly above the fulcrum pin 62. Themain linkage 56, pivotably connected thereto at pin 64, follows along.This causes the distal portion 56C of the main linkage 56 to move bothforwardly or proximally and upwardly between the housing side walls 24,26. In turn, the locking pawl 58 pivots on the housing pivot pin 72(arrow 102) to move its hook portion 68 from a closely spacedrelationship with the housing nose opening 50A to a second position,spaced further away from the nose opening than the first position.

As shown in the drawings, a surgical rasp 12, or similar tool comprisinga body designed to wear or cut bone and cartilage by friction, is nowmountable onto the handle assembly 10. The surgical tool 12 is providedwith an inlet 76 (FIG. 4) and an extension 78 aligned vertically abovethe inlet. The inlet 76 is sized and configured to receive the housingreinforcing nose 52 in a snug, but slidable fit. The extension 78 is nowreceived in the nose opening 50A with a locking indentation 78A alignedwith the hook portion 68 of the locking pawl 58. A locked relationshipbetween the handle assembly 10 and the surgical tool 12 is affected whenthe handle lever 54 is returned to its original position (arrow 104,FIG. 6), resting against the ledge 44. This return movement causes thelock pawl 58 to pivot on the housing pivot pin 70 (arrow 106) to movethe hook portion 68 back to the closely spaced relationship with thehousing nose opening 50A, to thereby reside in the indentation 78A ofthe surgical tool extension 78. As the locking pawl 58 pivots back toits original position, the main linkage 56 moves proximally. Thesurgical tool 12 is now firmly locked and secured to the handle assembly10 for use during a surgical procedure.

As shown in FIG. 6, the drive train 14 is locked into position once thefirst pivot pin 64 is proximal the fulcrum pivot pin 62 in an “overcenter” relationship. The over center, locked condition is indicated byarrow 80 as the gap between the two dashed lined centered on pins 62 and64 with respect to the center of the second pivot pin 70. The surgicaltool 12 is now firmly locked and secured to the handle assembly 10 foruse during a surgical procedure.

The special relationship between the axial handle region 22A extendingalong axis A-A and the radiused handle region 22B curving about thefocal point 32 (FIG. 3) is a unique feature of the present handleassembly 10. This structure provides a relatively short connectiondistance from the handle assembly 10 to the surgical tool 12 that isoptimum in the tight space requirements of a minimally invasive surgery,such as a hip surgery.

To prepare the handle assembly 10 for cleaning and sterilization, thelinkage lock mechanism 74 is manipulated in a direction away from thehousing 16 until the blocking pins 74B, 74C are completely removed fromthe bores 38A, 38B in the respective side walls 24, 26. The linkagetrain 14 including the handle lever 54 and main linkage 56 is nowpivotable out of the housing 16 about housing pivot pin 72. The pivotpin 72 keeps the linkage train 14 from being completely separated fromthe housing 16. Thus, the linkage train 14 is separable from the housing16 in a manner that is sufficient to clean and sterilize all of theirparts without the possibility of there being total separation of one forthe other. Total separation could easily lead to lost and misplacedparts.

The present invention further relates to the handle assembly 10comprising part of a kit. Typically, a surgical kit comprises acontainer, the handle assembly 10, and a surgical tool 12 to beconnected to the handle assembly. Representative surgical tools 12include, but are not limited to, broaches, rasps, reamers, angleddrivers, twist drills, flexible drills, cannulated drills, bayonetdrills, bayonet taps, drill guides, adjustable angle drill guides, taps,and cannulated taps. Instructions for connecting the surgical tool tothe handle assembly 10 are also typically provided with the kit.

Additionally, the linkage train 14 and housing 16 are preferably made ofa durable material that can be washed and sterilized (e.g., with highheat) to comply with sterilization standards known in the art. In oneembodiment, the linkage train 14 and housing 16 are made of metal, suchas stainless or a super alloy material. In another embodiment, they aremade of a composite material. Though the illustrated embodiment showsthe housing 16 as being one piece, in other embodiments it can bemodular to facilitate disassembly of the handle assembly 10.

Of course, the foregoing description is that of certain features,aspects and advantages of the present invention, to which variouschanges and modifications can be made without departing from the spiritand scope of the present invention. Moreover, the handle assembly neednot feature all of the objects, advantages, features and aspectsdiscussed above. Thus, for example, those of skill in the art willrecognize that the invention can be embodied or carried out in a mannerthat achieves or optimizes one advantage or a group of advantages astaught herein without necessarily achieving other objects or advantagesas may be taught or suggested herein. In addition, while a number ofvariations of the invention have been shown and described in detail,other modifications and methods of use, which are within the scope ofthis invention, will be readily apparent to those of skill in the artbased upon this disclosure. It is contemplated that various combinationsor sub-combinations of these specific features and aspects embodimentsmay be made and still fall within the scope of the invention.

What is claimed is:
 1. A surgical tool handle, which comprises: a) ahousing providing a linkage chamber extending from a proximal housinggrip end to a distal housing tool end for receiving a tool; b) a toollinkage at least partially housed within the linkage chamber, the toollinkage comprising: i) a handle lever attached to the housing by aproximal housing pivot pin to thereby provide a first pivotableconnection between the tool linkage and the housing; ii) a locking pawlattached to the housing by a distal housing pivot pin to thereby providea second pivotable connection between the tool linkage and the housing;and iii) a main linkage comprising a proximal main linkage end connectedby a first free pivot pin to the handle lever adjacent to the proximalhousing end in a third pivotable connection and a distal main linkageend connected by a second free pivot pin to the locking pawl adjacent tothe distal housing end in a fourth pivotable connection; and c) whereinthe handle lever is pivotable about the proximal housing pivot pin froma first, opened position spaced a maximum distance along a range ofmotion from the proximal housing end to a second, closed position spacedat a closer distance along the range of motion relative to the proximalhousing end than the first position to thereby cause the main linkage,connected to the handle lever by the first free pivot pin, to move in aproximal direction toward the proximal housing end, to thereby cause thelocking pawl, connected to the distal main linkage end by the secondfree pivot pin, to pivot with respect to the housing on the distalhousing pivot pin from an open configuration ready to receive a tool forattachment to the housing to a closed configuration engageable with atool supported at the distal housing tool end.
 2. The surgical toolhandle of claim 1 wherein the proximal housing pivot pin is supported onthe housing in a pair of catch recesses at a position that is distal theproximal housing end, to pivotably mount the handle lever to thehousing.
 3. The surgical tool handle of claim 2 wherein the proximalhousing pivot pin is selectively removable from the pair of catchrecesses provided in the housing.
 4. The surgical tool handle of claim 1wherein the distal housing pivot pin is not separable from the housing.5. The surgical tool handle of claim 1 wherein with the handle lever inthe second, closed position, the second pivotable connection between theproximal main linkage end and the handle lever at the first free pivotpin is more proximal than the first pivotable connection of the handlelever and the housing at the proximal housing pivot pin.
 6. The surgicaltool handle of claim 1 wherein the distal housing pivot pin pivotallysupports the tool linkage for pivotable movement, out of the linkagechamber for cleaning with the tool linkage remaining connected to thehousing at the second pivotable connection of the distal housing pivotpin.
 7. The surgical tool handle of claim 1 wherein the tool linkage isremovably attached to the housing at the proximal housing pivot pin by alinkage lock mechanism such that when the linkage lock mechanism is in arelease position, the tool linkage is pivotable out of the linkagechamber for cleaning with the tool linkage remaining connected to thehousing at the second pivotable connection of the distal housing pivotpin.
 8. The surgical tool handle of claim 1 wherein linkage lockmechanism comprises a base plate supporting a pair of side-by-side pinsthat are received in the housing to block release of the proximalhousing pivot pin from removal out of a pair of catch recesses on thehousing.
 9. The surgical tool handle of claim 1 wherein a proximalsection of the housing is aligned along an axis A-A and a radiusedhousing section curves about a focal point.
 10. The surgical tool handleof claim 9 wherein the radiused housing section curves either in arightward or a leftward direction with respect to the axis A-A.
 11. Thesurgical tool handle of claim 9 wherein the housing comprises a bottomwall that is planar along the axial housing section, but not theradiused housing section.
 12. The surgical tool handle of claim 9wherein the locking pawl is disposed within a distal neck portion of thehousing, the distal neck portion being disposed along an axis B-B thatis parallel to, but spaced from, the axis A-A.
 13. The surgical toolhandle of claim 1 wherein a strike plate is attached to the housing atthe proximal housing end.
 14. The surgical tool handle of claim 1wherein a reinforcing extension is provided at the distal housing toolend to reinforce a connection between the handle and a surgical tool.15. The surgical tool handle of claim 1 wherein the locking pawl changesplanes from a proximal locking pawl end to a distal extending hook endengageable with a surgical tool.
 16. A kit, comprising: a) a container;b) a surgical tool handle according to claim 1, wherein the surgicaltool handle is disposed within the container; and c) a tool to beconnected to the surgical tool handle, wherein the tool is selected froma group consisting of broaches, rasps, reamers, angled drivers, twistdrills, flexible drills, cannulated drills, bayonet drills, bayonettaps, drill guides, adjustable angle drill guides, taps, and cannulatedtaps.
 17. The kit of claim 16 comprising instructions for connecting thetool to the surgical tool handle.